don't crash LibCecSharp when receiving an alert with a NULL param (like the connectio...
[deb_libcec.git] / src / lib / CECInputBuffer.h
1 #pragma once
2 /*
3 * This file is part of the libCEC(R) library.
4 *
5 * libCEC(R) is Copyright (C) 2011-2013 Pulse-Eight Limited. All rights reserved.
6 * libCEC(R) is an original work, containing original code.
7 *
8 * libCEC(R) is a trademark of Pulse-Eight Limited.
9 *
10 * This program is dual-licensed; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
14 *
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
19 *
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to the Free Software
22 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
23 *
24 *
25 * Alternatively, you can license this library under a commercial license,
26 * please contact Pulse-Eight Licensing for more information.
27 *
28 * For more information contact:
29 * Pulse-Eight Licensing <license@pulse-eight.com>
30 * http://www.pulse-eight.com/
31 * http://www.pulse-eight.net/
32 */
33
34 #include "platform/threads/mutex.h"
35 #include "platform/util/buffer.h"
36
37 namespace CEC
38 {
39 // a buffer that priotises the input from the TV.
40 // if we need more than this, we'll have to change it into a priority_queue
41 class CCECInputBuffer
42 {
43 public:
44 CCECInputBuffer(void) : m_bHasData(false) {}
45 virtual ~CCECInputBuffer(void)
46 {
47 Broadcast();
48 }
49
50 void Broadcast(void)
51 {
52 PLATFORM::CLockObject lock(m_mutex);
53 m_bHasData = true;
54 m_condition.Broadcast();
55 }
56
57 bool Push(const cec_command &command)
58 {
59 bool bReturn(false);
60 PLATFORM::CLockObject lock(m_mutex);
61 if (command.initiator == CECDEVICE_TV)
62 bReturn = m_tvInBuffer.Push(command);
63 else
64 bReturn = m_inBuffer.Push(command);
65
66 m_bHasData |= bReturn;
67 if (m_bHasData)
68 m_condition.Signal();
69
70 return bReturn;
71 }
72
73 bool Pop(cec_command &command, uint16_t iTimeout)
74 {
75 bool bReturn(false);
76 PLATFORM::CLockObject lock(m_mutex);
77 if (m_tvInBuffer.IsEmpty() && m_inBuffer.IsEmpty() &&
78 !m_condition.Wait(m_mutex, m_bHasData, iTimeout))
79 return bReturn;
80
81 if (m_tvInBuffer.Pop(command))
82 bReturn = true;
83 else if (m_inBuffer.Pop(command))
84 bReturn = true;
85
86 m_bHasData = !m_tvInBuffer.IsEmpty() || !m_inBuffer.IsEmpty();
87 return bReturn;
88 }
89
90 private:
91 PLATFORM::CMutex m_mutex;
92 PLATFORM::CCondition<volatile bool> m_condition;
93 volatile bool m_bHasData;
94 PLATFORM::SyncedBuffer<cec_command> m_tvInBuffer;
95 PLATFORM::SyncedBuffer<cec_command> m_inBuffer;
96 };
97 };